Publication-bias evidence differs by subset: significant funnel-plot asymmetry for course-embedded spacing studies but no strong evidence of bias for isolated-material studies.¶

Claim · All claims
Evidence · 1 study (2 entries) · quant-synthesis r3 · q3
Currency · newest study 2023 · not yet checked against its sources · not reviewed by a person

Subclaims¶

q3 i? Egger's regression test was significant for the course-embedded subset (t = -2.4, d.f. = 24, p = 0.025) but not for the isolated subset (t = 0.87, d.f. = 21, p = 0.394). → Murray 2023 q3 i? For the isolated subset, the funnel plot appeared asymmetric but Egger's test and trim-and-fill found no significant evidence of publication bias. → Murray 2023 (2)

Evidence¶

Murray 2023¶

Murray, E., Horner, A. J., & Göbel, S. M. (2023). A Meta-analytic Review of the Effectiveness of Spacing and Retrieval Practice for Mathematics Learning. https://osf.io/

q3 · i? · quant-synthesis · r3

Risk-of-bias analysis of the course-embedded spacing subset. The significant Egger's test suggested publication bias; trim-and-fill added 6 studies with a corrected effect of "g= 0.27[0.215, 0.326]".

"Egger’s regression test for funnel plot asymmetry is significant (t = -2.4, d.f. = 24, p = 0.025) suggesting publication bias resulting from insignificant results remaining unpublished."

Murray 2023 (2)¶

Murray, E., Horner, A. J., & Göbel, S. M. (2023). A Meta-analytic Review of the Effectiveness of Spacing and Retrieval Practice for Mathematics Learning. https://osf.io/

q3 · i? · quant-synthesis · r3

Risk-of-bias analysis of the isolated-material spacing subset. Despite visible funnel-plot asymmetry, neither Egger's test nor trim-and-fill (which added no studies) indicated significant statistical evidence of publication bias.

"An insignificant Egger’s regression test for funnel plot asymmetry (t = 0.87, d.f. = 21, p = 0.394) does not suggest publication bias resulting from non-significant results remaining unpublished."

Discussion¶

Related Claims¶

• Funnel-plot asymmetry ran contrary to small-study effects because larger-sample studies reported larger effect sizes, likely reflecting longer training programs — related
• When spacing is embedded into a course, spaced practice retains a robust but numerically smaller effect (g = 0.24) than for isolated material. — related
• Funnel-plot asymmetry indicates small-study effects for some emotion–learning models — related
• Publication-bias tests (Egger's test and trim-and-fill) indicate absence of publication bias for the overall effect and moderators — related
• Publication bias evidence is mixed: marginal asymmetry for tutees but no missing studies, and no bias for tutors — related
• Publication-bias checks indicate limited risk of publication bias in the extensive reading literature synthesized — related
• The ratio–interactive-skills association may be partly or entirely attributable to small-study publication bias — related